Am I crazy or is something wrong...

I have an Ampeg 410HEN cab and i'm powering it with a QSC RMX 1450 with a Sansamp RBI. Lastnight i had a gig and I had to turn the power amp and the pre almost all the way up to hear myself over everything. Is that normal or might something be wrong? Please let me know. thanks.

Well, if you didn't bridge the power amp, then the power sent to this 8 ohm cab is 280 W at a maximum, according to QSC RMX-1450 specs .

Even worse, if you have to crank it up all the way, you may cause severe damage to the speakers by generating some kind of "buzzing" distorsion.

I'd suggest that you bridge the amp. You will then be able to send 900 W to your cab. Though, IMO you should care to adjust power amp level halfway, which should be more than enough in most cases, unless your guitarist plays through a wall of Triple Rectifiers...

You can power it with a million watts and it won't matter. Check out the thread on power compression. Anything over 1/2 of the cabinet's rating just gets burned off as heat. Being a 4x10 and assuming you have it on the floor the likely problem is that the midrange frequencies critical to your being able to hear what you are playing, which are extremely directional in a 4x10, aren't reaching your ears. Tilt the cabinet back.

+1 on the bridging into 8ohms... and also check to make sure you do not have too 'scooped' of an EQ curve on your preamp.

Tilting back a 410 to hear better? If you have the EQ set 'correctly', you should have no problem hearing the 410, and you probably need all the floor coupling you can get, since it sounds like you are playing at pretty high volumes.

Tilting back a 410 to hear better? If you have the EQ set 'correctly', you should have no problem hearing the 410, and you probably need all the floor coupling you can get, since it sounds like you are playing at pretty high volumes

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You don't lose coupling by tilting the cab. Even if you went so far as to lie it on its back it would still be radiating into half space as far as the bass frequencies are concerned. The problem lies in the midrange,and it has nothing to do with EQ. A 4x10 cab is a wavelength high from about 500 Hz, above which dispersion on the vertical plane gets very narrow. With the cab pointing straight if you stand too close you won't be able to hear the midrange because your ears aren't within the midrange beamwidth. The non-directional bass frequencies may be there, but the ear is less sensitive to bass frequencies than midrange by as much as a 10:1 ratio. If the loudest sources of midrange frequencies that he's hearing on stage are coming from instruments other than his own he'll hear them, not himself. Tilting the cab back a few degrees is the easiest way to prevent that.

You don't lose coupling by tilting the cab. Even if you went so far as to lie it on its back it would still be radiating into half space as far as the bass frequencies are concerned. The problem lies in the midrange,and it has nothing to do with EQ. A 4x10 cab is a wavelength high from about 500 Hz, above which dispersion on the vertical plane gets very narrow. With the cab pointing straight if you stand too close you won't be able to hear the midrange because your ears aren't within the midrange beamwidth. The non-directional bass frequencies may be there, but the ear is less sensitive to bass frequencies than midrange by as much as a 10:1 ratio. If the loudest sources of midrange frequencies that he's hearing on stage are coming from instruments other than his own he'll hear them, not himself. Tilting the cab back a few degrees is the easiest way to prevent that.

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Makes sense... I never had this problem with a 410, but maybe I'm too old and not playing loud enough anymore!!!!

2. The RBI has a notoriously low output. The QSC might not be seeing enough signal to drive it to it's rated capacity.

3. If the 4x10 is on the floor, and you're standing close in, the majority of the sound is blowing out past your knees. An amp stand would be a real help here. I run my 2x10 on a tilt back stand and have no complaints.